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Ion heat transport in electron cyclotron resonance heated L-mode plasma on the T-10 tokamak

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Plasma Science and Technology 2024年第4期26卷 52-60页

作者： V.A.KRUPIN M.R.NURGALIEV A.R.NEMETS I.A.ZEMTSOV S.D.SUNTSOV T.B.MYALTON D.S.SERGEEV N.A.SOLOVEV D.V.SARYCHEV D.V.RYJAKOV S.N.TUGARINOV N.N.NAUMENKO National Research Centre“Kurchatov Institute” Moscow 123182Russia bauman moscow state technical university Moscow 105005Russia Institution“Project Center ITER” Moscow 123098Russia JSC“SOLAR” Minsk 220034Belarus

Anomalous ion heat transport is analyzed in the T-10 tokamak plasma heated with electron cyclotron resonance heating(ECRH) in second-harmonic extra-ordinary mode. Predictive modeling with empirical scaling for Ohmical heat conductivity shows that in ECRH plasmas the calculated ion temperature could be overestimated, so an increase of anomalous ion heat transport is required. To study this effect two scans are presented: over the EC resonance position and over the ECRH power. The EC resonance position varies from the high-field side to the low-field side by variation of the toroidal magnetic field. The scan over the heating power is presented with on-axis and mixed ECRH regimes. Discharges with high anomalous ion heat transport are obtained in all considered regimes. In these discharges the power balance ion heat conductivity exceeds the neoclassical level by up to 10 times. The high ion heat transport regimes are distinguished by three parameters: the ratio Te/Ti, the normalized electron density gradient R/■, and the ion–ion collisionality νii~*. The combination of high Te/Ti, high νii~*, and R/■=6-10 results in values of normalized anomalous ion heat fluxes up to 10 times higher than in the low transport scenario.

关键词： tokamak L-mode electron cyclotron resonance heating ion heat transport

Determination of Thermal Properties of Unsmooth Si Nanowires

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Chinese Physics Letters 2024年第1期41卷 51-56页

作者：刘世贤 Alexander A.Barinov 訚菲 Vladimir I.Khvesyuk Department of Thermophysics Bauman Moscow State Technical UniversityMoscow 105005Russian Federation

We estimate the thermal properties of unsmooth Si nanowires,considering key factors such as size(diameter),surface texture(roughness)and quantum size effects(phonon states)at different *** nanowires with a diameter of less than 20 nm,we highlight the importance of quantum size effects in heat capacity calculations,using dispersion relations derived from the modified frequency equation for the elasticity of a *** thermal conductivities of nanowires with diameters of 37,56,and 115nm are predicted using the Fuchs–Sondheimer model and Soffer’s specular ***,the roughness parameters are chosen to reflect the technological characteristics of the real *** findings reveal that surface texture plays a significant role in thermal conductivity,particularly in the realm of ballistic heat transfer within *** study provides practical recommendations for developing new thermal management materials.

关键词： nanowires roughness size

A New Generation of Rules-based Approach:Mivar-based Intelligent Planning of Robot Actions(MIPRA)and Brains for Autonomous Robots

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Machine Intelligence Research 2024年第5期21卷 919-940页

作者： Oleg Varlamov Dmitry Aladin Department of Information Processing and Management Systems RI MIVARBauman Moscow State Tchnical University(BMSTU)Moscow105005Russian Federation

To create autonomous robots,both hardware and software are *** enormous progress has already been made in the field of equipment,then robot software depends on the development of artificial *** article proposes a solution for creating“logical”brains for autonomous robots,namely,an approach for creating an intelligent robot action planner based on Mivar expert *** application of this approach provides opportunities to reduce the computational complexity of solving planning problems and the requirements for the computational characteristics of hardware platforms on which intelligent planning systems are *** theoretically and practically justify the expediency of using logically solving systems,in particular Mivar expert systems,to create intelligent planners,the MIPRA(Mivar-based Intelligent Planning of Robot Actions)planner was created to solve problems such as STRIPS for permutation cubes in the Blocks World *** planner is based on the platform for creating expert systems of the *** a result,the Mivar planner can process information about the state of the subject area based on the analysis of cause-effect relationships and an algorithm for automatically constructing logical inference(finding a solution from“Given”to“Find”).Moreover,an important feature of the MIPRA is that the system is built on the principles of a“white box”,due to which the system can explain any of its decisions and provide justification for the actions performed in the form of a retrospective of the stages of the decision-making *** preparing a set of robot actions aimed at changing control objects,expert knowledge is used,which is the basis for the functioning algorithms of the *** approach makes it possible to include an expert in the process of organizing the work of the intelligent planner and use existing knowledge about the subject *** experiments of this study have shown that instead of many hours and powerfu

关键词： Autonomous robot blocks world decision-making system expert systems intelligent planning

A Review on the Influence of In-cylinder Turbulence Type on Combustion Characteristics of High Power-Density Diesel Engine

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Journal of Traffic and Transportation Engineering(English Edition) 2024年

作者： Zhongxi Tong Han Wu Zhicheng Shi Leonid Myagkov School of Mechanical Engineering， Beijing Institute of Technology Department of Piston Engines， bauman moscow state technical university

With the continuous improvement of performance requirements， direct injection diesel engines have gradually developed towards more small， lightweight， and high power， named as high power-density. It needs more injected fuel can be mixed and burn at the same duration time to guarantee the thermal-power conversion effects. It is required that the combustion system has a fast mixing speed of fuel and gas， and a fast combustion speed. Organizing appropriate cylinder turbulence is an effective means of optimizing combustion to reach requirements. The current work is aim to investigates and summarizes the influence of different types of in cylinder turbulence coursed by intake， spray， and combustion chamber configuration on the performance of a highly intensified diesel engine from the three causes of turbulence. The comparative study found that the adoption of a separate combustion chamber， the increase of intake swirl and number of nozzles can have positive effect on the optimization of the combustion process of a highly intensified diesel engine， but for different combustion chamber types， the influence of intake swirl and spray parameters was different. The separated combustion chamber is more sensitive to spray parameters than the combustion chamber without wall guide design. Compared with the transverse separated combustion chamber， the longitudinal separated combustion chamber is more suitable for large intake swirl ratio. For a specific combustion chamber structure， both intake swirl and spray parameters have optimal values.

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Double-AOTF-based aberration-free spectral imaging endoscopic system for biomedical applications

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Journal of Innovative Optical Health Sciences 2015年第3期8卷 72-77页

作者： Alexander Machikhin Vitold Pozhar Vladislav Batshev Scientic and Technological Center of Unique Instrumentation RAS Butlerova street 15Moscow 117342Russia bauman moscow state technical university 2nd baumanskaya street 5Moscow 105005Russia

The problem of in vrivo photoluminescence diagnostics of the tissues acessible by endoscopes is *** spectral imaging module attachable to conventional rigid and flexible medical endoscopes is developed and *** is based on a double acousto-optical tunable filter(AOTF)and a specialized optical coupling *** module provides wide field of view(FOV),absence of image distortions,random spectral access,fast spectral image acquisition at any wavelength in the visible range and accurate measurement of reflectance spectrum in each pixel of the *** of typical biomedical samples are presented and *** spectra are compared to the reference data.

关键词： Spectral imaging spectrasoopy double monochromatization acousto-optical tunable fiter photoluminescence diagnostics endoscopy

High-speed performance self-powered short wave ultraviolet radiation detectors based onκ(ε)-Ga_(2)O_(3)

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Journal of Semiconductors 2024年第4期45卷 56-62页

作者： Aleksei Almaev Alexander Tsymbalov Bogdan Kushnarev Vladimir Nikolaev Alexei Pechnikov Mikhail Scheglov Andrei Chikiryaka Petr Korusenko Research and Development Center for Advanced Technologies in Microelectronics National Research Tomsk State UniversityTomsk 634050Russia Fokon LLC Kaluga 248035Russia Department of Semiconductor Electronics and Physics of Semiconductors National University of Science and Technology MISISMoscow 119049Russia Perfect Crystals LLC Saint Petersburg 194223Russia Department of Solid-state Electronics Saint Petersburg State UniversitySaint Petersburg 199034Russia Department of Physics Omsk State Technical UniversityOmsk 644050Russia

High-speed solar-blind short wavelength ultraviolet radiation detectors based onκ(ε)-Ga_(2)O_(3)layers with Pt contacts were demonstrated and their properties were studied in ***κ(ε)-Ga_(2)O_(3)layers were deposited by the halide vapor phase epitaxy on patterned GaN templates with sapphire *** spectral dependencies of the photoelectric properties of struc-tures were analyzed in the wavelength interval 200-370 *** maximum photo to dark current ratio,responsivity,detectiv-ity and external quantum efficiency of structures were determined as:180.86 ***.,3.57 A/W,1.78×10^(12) Hz^(0.5)∙cm·W^(-1) and 2193.6%,respectively,at a wavelength of 200 nm and an applied voltage of 1 *** enhancement of the photoresponse was caused by the decrease in the Schottky barrier at the Pt/κ(ε)-Ga_(2)O_(3)interface under ultraviolet *** detectors demon-strated could functionalize in self-powered mode due to built-in electric field at the Pt/κ(ε)-Ga_(2)O_(3)*** responsivity and external quantum efficiency of the structures at a wavelength of 254 nm and zero applied voltage were 0.9 mA/W and 0.46%,*** rise and decay times in self-powered mode did not exceed 100 ms.

关键词： κ(ε)-gallium oxide solar-blind shortwave ultraviolet radiation detectors self-powered operation mode

Predicting effects of tunnel throttling of annular freeway vehicular flow by a continuum model

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 733-746页

作者： Zhongmin Huang M.N.Smirnova N.N.Smirnov Zuojin Zhu Faculty of Engineering Science University of Science and Technology of ChinaHefei 230026China Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Faculty of Mechanics and Mathematics Lomonosov Moscow State UniversityMoscow 119992Russia

Fluid flow throttling is common in industrial and building services *** tunnel throttling of vehicular flow is caused by the abrupt number reduction of roadway lane,as the tunnel has a lower lane number than in the roadway normal *** predict the effects of tunnel throttling of annular freeway vehicular flow,a three-lane continuum model is ***Ⅲof the tunnel is completely blocked due to the need of tunnel rehabilitation,*** exists mandatory net lane-changing rate from laneⅢto laneⅡjust upstream of the tunnel entrance,which is described by a model of random number generated through a golden section *** net-changing rate between adjacent lanes is modeled using a lane-changing time expressed explicitly in algebraic *** paper assumes that the annular freeway has a total length of 100 km,a two-lane tunnel of length 2 km with a speed limit of 80 km/*** free flow speeds on lanesⅠ,ⅡandⅢare assumed to be 110,100 and 90 km/h *** on the three-lane continuum model,numerical simulations of vehicular flows on the annular freeway with such a tunnel are conducted with a reliable numerical method of 3rd-order *** results reveal that the vehicular flow has a smaller threshold of traffic jam formation in comparison with the case without tunnel *** fuel consumption can be estimated by interpolation with time averaged grid traffic speed and an assumed curve of vehicle *** vehicle fuel consumption is lane number dependent,distributes with initial density concavely,ranging from 5.56 to 8.00 *** throttling leads to an earlier traffic jam formation in comparison with the case without tunnel throttling.

关键词： Effects of tunnel throttling Vehicle fuel consumption Travel time Threshold of traffic jam formation Continuum model

Applications of two electric arc plasma torches for the beneficiation of natural quartz

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International Journal of Minerals,Metallurgy and Materials 2019年第3期26卷 267-273页

作者： Yuri-Mikhailovich Grishin Long Miao Lev-Alekseevich Borisov Nikolay-Mikhailovich Serykh Alexey-Yurievich Kulagin Department of Thermal physics Bauman Moscow State Technical University Federal state Unitary Enterprise Tsentrkvarts

Experimental beneficiation processes of quartz concentrate in arc plasma torches of two different types and electric powers were studied. An emission scanning electron microscope and a universal laser analyzer were used to investigate the structures as well as the size distributions of grains and microparticles. Inductively coupled plasma–mass spectrometry was used to determine the chemical compositions of nonstructural solid-phase mineral impurities in quartz concentrate. Results related to the modified grains' structure and size distribution, the compositions of impurities, and the gas–liquid inclusions in the quartz concentrate were investigated. The total impurities concentrations in the processed grains were found to satisfy the IOTA-STD standard(industry standard for grading high quality fused quartz products). The optimal condition(i.e., the optimal specific plasma enthalpy) for the production of high-purity quartz in arc plasma torches was found to depend on the geological-genetic type and the structural and textural features(i.e., chemical composition and gas–liquid inclusions) of the quartz concentrate.

关键词： low-temperature plasma beneficiation high purity quartz arc plasma torch IOTA-STD standard

Dynamic Modeling of the Feed Drive System of a CNC Metal Cutting Machine

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Sound & Vibration 2021年第1期55卷 19-30页

作者： H.Heydarnia I.A.Kiselev M.M.Ermolaev S.Nikolaev Department of Applied Mechanics Bauman Moscow State Technical UniversityMoscowRussia Department of Bases of Machine Designing Bauman Moscow State Technical UniversityMoscowRussia Skolkovo Institute of Science and Technology MoscowRussia

Studying the vibrational behavior of feed drive systems is important for enhancing the structural performance of computer numerical control(CNC)*** preload on the screw and nut position have a great influence on the vibration characteristics of the feed drive as two very important operational *** acceleration of the screw also affects the performance of the CNC feed drive when machining small *** paper investigates the influence of preload and nut position on the vibration characteristics of the feed drive system of a CNC metal cutting machine in order to be able to eliminate an observed resonance occurred at high rotational speeds of the screw,corresponding to high feed ***,rational structural parameters of the feed drive system are selected in order to increase the rotational acceleration for improving the performance of the CNC *** and analyses showed that by selecting specific parameters of feed drive system and simultaneously applying a certain value of preload,a 97%increase in rotational acceleration and 30%time reduction considering the vibration resistance at high rotational speeds can be achieved.

关键词： Machining performance CNC machine tools vibration characteristics machine tool dynamic modeling